Request your FNMT digital certificate
The procedure has a catch: the steps must be done in order and from the same browser. We guide you so you leave with the certificate installed first time.
- Category
- Compliance
- Level
- Beginner
- Time
- ≈ 30 min + identity check
- Steps
- 5
- Updated
- July 2026
Before you start.
What you are about to solve.
The FNMT (Fábrica Nacional de Moneda y Timbre, the Spanish Royal Mint) digital certificate is the electronic document that identifies you to the AEAT (Spanish Tax Agency) and authenticates your VeriFactu invoices. It is free, but obtaining it follows a strict order that confuses many people: you request it, verify your identity in person (or with the electronic ID card, DNIe) and only then download it. Skipping the order is the number one cause of failure.
There are two types depending on how you invoice: the natural-person certificate (for self-employed people, with your DNI) and the legal-entity representative certificate (for companies). Choose the right one before you start, because they are not interchangeable.
This guide takes you through the three moments (request, verification and download) with the details the official site takes for granted. Once you have it, upload it to Cofactu with the certificate guide and start invoicing.
Do it in order.
Open only the step you are on.
5 steps to review, issue and leave the document ready, without reading a whole guide at once.
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Prepare the browser before you start
Step 01: Prepare the browser before you start
The FNMT ties the request and the download to the same computer and browser, through a key generated on your machine. Choose a browser and do not change it throughout the process. Install the FNMT key-generation software if it asks you to. Do not format or clean the computer between the request and the download.
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Request the certificate on the FNMT website
Step 02: Request the certificate on the FNMT website
Go to the FNMT portal (Ceres), choose "Obtain software certificate" for natural person or representative depending on your case, and enter your NIF, first surname and an email. You will receive a request code by email. Keep it: you need it to verify your identity and to download.
- Natural person: for self-employed people and individuals, with the DNI.
- Legal-entity representative: to sign on behalf of a company.
- Write down the request code that arrives by email.
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Verify your identity
Step 03: Verify your identity
With the request code, you have to prove you are who you say. There are two routes: in person at an accreditation office (many AEAT and Social Security offices do it, normally by appointment), bringing your DNI and the code; or online if you already have a DNIe or video-identification available. Without this step you cannot download.
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Download and install the certificate
Step 04: Download and install the certificate
Once verified (the FNMT takes a while to enable it), go back to the FNMT website from the SAME computer and browser, enter "Download certificate", enter your NIF, surname and the request code again, and download it. It will be installed in the browser.
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Export it to a .p12 file
Step 05: Export it to a .p12 file
To use it outside the browser (for example in Cofactu), export the certificate to a .p12 (or .pfx) file including the private key, and set a password. This file is the one you will upload to Cofactu. Keep it somewhere safe and make a copy: it is your digital identity.
- In the browser: certificate options → export → include private key → PKCS#12 (.p12) format.
- Set a password you will remember: Cofactu will ask for it when you upload.
When you finish you will have your FNMT certificate installed and exported as a .p12 file, ready to upload to Cofactu and start authenticating and sending VeriFactu invoices.
The questions that come up
when you put it into practice.
Does the FNMT certificate cost money?
No, the FNMT natural-person certificate is free. The legal-entity representative one is also obtained through the FNMT; some specific cases may carry a fee. In-person verification at an office has no cost either.
How long does the whole process take?
The request and the download take minutes each, but in between is the identity verification: if in person, it depends on the appointment at your office (from days to a couple of weeks depending on the area). With a DNIe the verification is online and immediate.
Can I use the electronic ID card (DNIe) instead of the FNMT certificate?
The DNIe works for many procedures and even to verify yourself online when requesting the FNMT one. For unattended invoice authentication in Cofactu an FNMT certificate as a .p12 file is more practical, because the DNIe requires the physical reader on every use.
I already have the certificate, what now?
Upload it to Cofactu: in Settings → Certificates add the .p12 file with its password and it is stored encrypted and ready to authenticate your invoices. The detail is in the guide to setting up the digital certificate.
Continue from here.
Without losing context.
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